Modified polyamides and polyesters



March 1, 1966 F. wlLoTH MODIFIED POLYAMIDES AND POLYESTERS Filed Feb.12, 1962 O m ON O. O

INVENTOK FRITZ WILOTH BY Wl ATT'YS United States Patent O 3,238,180MODIFIED POLYAMIDES AND POLYESTERS Fritz Wiloth, Klingenberg, Germany,assignor to Vereinigte Glanzstoff-Fabriken AG., Wuppertal-Elberfeld,Germany Filed Feb. 12, 1962, Ser. No. 172,823 Claims priority,application Germany, Feb. 14, 1961,

Claims. (Cl. 260--47) This invention relates to modified polyamides andpolyesters having enhanced properties, and more particularly, theinvention is concerned with an improvement in those polyamides andpolyesters which are generally classified as synthetic fiber-forminglinear polymers. These polymers may also be classified as linearcondensation polymers, sometimes referred to as polycondensates.

The most common fiber-forming polyamides are those obtained fromcaprolactam or hexamethylene adipamide, while the most widely acceptedfiber-forming polyester is polyethylene terephthalate. Thesepolycondensates and closely related polyamides and polyesters haveproperties which make them especially suitable for the production ofsuch textile products as filaments, staple fibers, thread, fabrics,knitted textiles and the like as well as for the production of a numberof other useful articles. However, there are certain fiber properties orqualities which are lacking in fully synthetic polymers by comparisonwith natural or regenerated fibrous polymers. For example, with specialconcern for the use of -polyamides and polyesters for application in thetextile industry, it would be highly desirable to obtain an improvementin such fiber properties as water absorptivity, washability, dyeabilityand electrical conductivity or antielectrostatic behavior. Moreover, itwould be especially helpful if these particular properties could beimproved in a controlled manner so as to provide a tailor-made product.Moreover, the improvement in the aforementioned properties should beaccomplished Without substantially detracting from such properties astensile strength, elongation, melting point and the like.

It has been established in the lprior art that fibers of 4syntheticpolyamides and polyesters differ considerably from natural fibers insuch properties as water absorp- Vtivity, washability, dyeability andantielectrostatic behavior. For example, the capacity for waterretention, determined according to DIN53814 E (German IndustrialStandard), is commonly designated in textile technology as the swellingvalue, and a comparison of this value for typical synthetic and naturalfibers is about as follows: 11% for polycaprolactam, 10.5% forpolyhexamethylene adipamide, 3% for polyethylene terephthalate, and onthe other hand, from 40 to 50% for cotton and wool. Similarly, the drymoisture absorption (measured at C. and 65% relative humidity), is about4% for polycaprolactam and polyhexamethylene adipamide and about 0.4%for polyethylene terephthalate, whereas this value is about 8% `forcotton and about 12% for wool. It is also well known that natural fibersgenerally have much better affinity for dyestuffs than do the syntheticfibers, and the antielectrostatic behavior and washability of naturalfibers is usually better than the synthetic fibers. Therefore, thepotential for improvement in polyamide and polyester fibers is wellestablished, but a solution to the various problems involved has beenmost difficult.

One method of influencing such properties of synthetic fibers has beento impregnate or apply foreign substances to the fiber surface. However,such foreign substances tend to wear off or become washed away from thefiber so that an initial modification of the fiber property is not ICCdurable and is gradually lost when using the product. The employment oftextile auxiliaries or finishing preparations thus provides only atemporary solution to the problem, particularly with respect topolyamides and polyesters.

A large number of attempts have therefore been made to more stronglydevelop certain desired properties in synthetic polymers by makingstructural alterations in the polymer molecule itself. For example, withpolyamides and polyesters, the usual diamine and dicarboxylic acidmonomers have been substituted with various aliphatic and aromatic sidechains. The art further contains descriptions of polymers orpolycondensates in which the individual monomers contain a carbon chaininterrupted by a hetero-atom. Still another process suggests the use oftendo-cap-rolaetiam compounds las monomers for conversion into animproved polyamide. This alteration in the molecular structure of theknown monomers is often unsatisfactory because an improvement in oneparticular property of the resulting synthetic fiber causes adeterioration of other desirable properties. For example, an improvementin either water absorptivity or dyeability may also cause a tensilestrength or melting point which is much lower than the standardsrequired for a textile product. Thus, previous attempts tomodify themolecular structure of polyamides and polyesters have not led to anyappreciable commercial success, because the improvement in certain fiberproperties is either so lslight as to be negligible or else is achievedat the expense of other highly desirable properties such as a highmelting point. In some cases, the modification of the ploymer operatesselectively on only a single property, and it is quite difficult toobtain an overall improvement for textile purposes. Because of thegenerally slight effect of polymer substituents or additives, the priorart has never considered the possibility of providing a controlled orpredetermined modification of fiber properties.

One object of the present invention is to provide a durable andlsubstantially permanent improvement in the water-absorptivity,dyeability, washability and antielectrostatic behavior (i.e. electricconductivity) of the fiberforming polyamides and polyesters.

Another object of the invention is to provide improved 'polyamide andpolyester products by introducing a highly effective foreign buildingblock into the linear polymer chain of the polycondensate.

A particular object of the invention is to provide new and usefulcopolymers of polyamides and polyesters whereby it is possible tocontrollably influence in a predetermined manner the above-mentionedpolymer properties such as water-absorptivity and the like.

Still another object of the invention is to provide modified polyamidesand polyesters characterized by an overall improvement in properties fortextile applications, such that the resulting synthetic product moreclosely simulates such natural products -as cotton and wool.

Yet another particular object of the invention is to provide modifiedpolyamides and polyesters capable of acting as ion exchange substances,for example when ernployed as a porous fabric or as a permeable film ormembrane.

These and other objects and advantages of the invention will be morereadily appreciated upon consideration of the following detailedspecification.

It has now been found, in accordance with the 4invention, that syntheticfiber-forming linear polyamides and polyesters with highly improved andnovel properties can be obtained if they are modified so as to includeby condensation into the linear polymer chain a relatively small amountof certain phenoxy compounds or derivatives which contain special sidechain substituents. The substituted phenoxy compounds of the inventionare highly active and can be employed to influence a number of differentpolymer properties, and depending upon the concentration in which thephenoxy compounds are used and their specific structure, polyamides andpolyesters can be modified within relatively broad limits. The compoundsof the invention which are added as a modifying unit in the polymerchain are designated by the following formula:

(A) fl- C mHzm-Z l G wherein:

Z is a member selected from the group consisting of hydrogen, 03H andits alkali metal and ammonium salt, -NR1R2, -NGBR1R2R3XQ -NR1-CyH2y-SO3Hand NRlRg-CyI-Igyoge, D and E each represent a member selected from thegroup -COOR and -COO-CHZCHZOH G represents a member selected from thegroup consisting of alkyl, aryl and -O-CmH2m-Z R1, R2 and R3 eachrepresent a substituent selected from the group consisting of hydrogen,alkyl and aryl;

X represents halogen;

m is an integer of from 1 to 24, inclusive;

n is an integer of from to 12, inclusive; and

y is an integer of from 1 to 8, inclusive.

The function of each of the substituents or reactive groups in thephenoxy compound (A) can be described briefly as follows. The Z group,connected to the benzene nucleus through the oxyalkylene chain, acts tolimpart hydrophilic properties to the compounds (A) and to thepolyamides or polyesters in which such compounds are incorporated. Thedivalent alkylene linkage --C111H2m contain from l to 24 carbon atoms,with a higher number of carbon atoms such as 6 to 24 being preferredwhere Z is hydrogen and otherwise a preferred number of about l to l0carbon atoms.

The reactive groups D and E act as a means of condensing these compoundsinto the linear polymer chain of the polyamide and polyestermacromolecules, and D and E maybe identical or different groups. D and Emay be connected directly to the benzene nucleus but are preferablyattached through the alkylene bridge *C11H2- where n is equal to 1 to12.

The substituent G serves primarily the purpose of blocking the reactivepara-position of the basic phenolic compound employed in the synthesisof the compounds (A) and is therefore prefera-bly an inert or neutralalkyl or aryl hydrocarbon substituent, preferably lower alkyl such asmethyl, ethyl, propyl or butyl or a simple aryl group such as phenyl.However, G can also be selected to provide additional or strongerhydrophilic properties by using a longer chain alkyl radical of up to 24carbon .atoms or by using alkyl of 1 to 24 carbon atoms substituted byanother -O-CmH2m-Z group. Accordingly, G may be represented as where Ris again an alkylene radical of 1 to 24 carbon atoms, preferably l tocarbon atoms, or an aryl radical such as phenyl, and Z has the samemeaning as designated above.

The nitrogen substituents in the Z group as designated by R1, R2 and R3should be carefully selected in forming a purely linear polycondensate,free of cross-linking, such that the nitrogen atom is present in th-eform of a tertiary or quaternized amine, i.e. where R1 and R2 representonly alkyl or aryl while R3 represents alkyl, aryl or hydrogen. Thus, R3would be hydrogen in the HCl-salt of a tertiary amino group. Since thepresent invention contemplates a use of the polycondensates in the formof lms as Well as fibers, R1 and R2 may also be hydrogen where a certaindegree of cross-linking can be tolerated. Thus, in a film employed forits -ion exchange properties, the fiberforming properties of a trulylinear polymer are of secondary importance.

The lsubstituen-ts R' and R" in the groups D and E may be eitherhydrogen or an equivalent substituent such as'alkyl or aryl since groupsD and E will always bear at least one reactive hydrogen atom in aprimary or secondary amino group or their quaternized derivatives. WhereR" is employed in esterifying a carboxylic group, it is preferablymethyl so as to be readily split off and removed as methanol from anypolymerization medium. Otherwise, R and R" as well as R1, R2 and R3 arepreferably lower alkyl such as methyl, ethyl, propyl or butyl or an arylgroup such as phenyl. Where the groups D and E contain thesubstituent-NHAcyl, the acyl portion is preferably benzoyl or theresidue of a lower fatty acid, e.g. acetyl, propionyl or butyryl inorder to permit condensation polymerization to be easily carried out bysaponification or transamidation of these substituents The halogensubstituent X in any of the Z, D or E groups is preferably chlorine orbromine.

The present invention is not concerned with new polymers ascharacterized by the exclusive use of new monomers. Instead, theinvention is directed to the modification of known polyamides andpolyesters by the use of small amounts of a modifying monomer-iccompound (A) to form mixed polymers or copolymers, and in a narrowersense, graft and block polymers or interpolymers. The modifying unit canbe added to the known polyamide or polyester substances either before orduring polymerization of the monomers or to the known polymer afterthere has been substantially complete polycondensation but beforefurther processing into filaments, films or the like. The techniques ofpolycondensation, formation of block or graft polymers and similarpolymerization reactions are well known in this art, and conventionalpolymerization methods are employed in the present invention forincorporating the phenoxy compounds (A) in the polymer chain.

The poly-amides and polyesters to be modified according to the inventionare preferably those which normally have excellent primary fiberproperties, i.e. such mechanical or physical properties as tensilestrength, elongation and relatively high melting points, and there isnow a well-defined class of such fiber-forming polymers. For example,the fiber-forming polyamides are generally either polylactams, includingpolycaprolactam, polycaprylic lactam and polyoenanthic lactam, or elsethey are polycondensation products of a dicarboxylic acid and a diamine,polyhexamethylene adipamide being the most common example of a nylonpolyamide.

Suitable aliphatic dicarboxylic acids for preparing polyamides are thosewhich contain about 2 to 12 carbon atoms, preferably those containing 6to 10 carbon atoms, i.e. adipic acid, pimelic acid, suberic acid,azelaic acid and sebacic acid. Suitable aliphatic diamines to be used inconjunction with dicarboxylic acids in forming polyamides are thosecontaining about 4 to l2 carbon atoms and preferably 6 to 10 carbonatoms, e.g. tetramethylene diamine, pent-amethylene diamine,hexamethylene diamine, octamethylene diamine and dodecamethylenediamine. Of course, a single acid is usually paired with a single amine,and polymerization is most commonly carried out wit han acid-amine saltas the monomer, but mixtures of these components are also useful.

The known fiber-forming polyesters are prepared by polycondensing adicarboxylic acid, or more commonly its dimethyl ester, with a suitableglycol. Terephthalic acid or its dimethyl ester are most widely employedas the acid component while ethylene glycol is the most common glycolcomponent. Isophthalic acid has been employed to a much smaller extent,usually in combination with hexamethyl'ene glycol. Other dicarboxylicacids, which are usually employed as modifiers in an amount of up to l0molar percent, include sebacic, adipic, bibenzoic, naphthalic andhexahydroterephthalic acid. The glycol component generally contains fromabout 2 to 6 carbon atoms, including tetramethylene glycol,hexamethylene glycol and diethylene glycol in addition to ethyleneglycol.

As noted above, the modifying unit of the invention as derived from thephenoxy compounds (A) can be condensed into the known polyamides andpolyesters as initial monomers by addition before or during thepolymerization reaction or by addition after obtaining the knownpolycondensate so as to form a graft or block polymer. The termcondensed is employed herein in its broadest sense to include all of theknown procedures of forming linear polyamides and polyesters, eventhough the reaction proceeds lby ester interchange, transamidificationor that condensation in which a molecule of water or other smallmolecule such as methanol is split off and removed each time a linkageis formed. Thus, the polymerization of caprolactam can be considered asa condensation reaction in this broad sense, even when carried out underanhydr-ous cond-itions.

Depending upon the desired result during polycondensation, the modifyingunits of the invention can be incorporated in the polymer chain in anamount which is relatively small, e.g. about 0.1 molar percent up to arelatively large amount of about 10 molar percent. In m-ost instances,it is preferred to employ the modifying agent of the invention in anamount of about 0.15 or 0.2 up to about 2 molar percent. The term molarpercent is employed herein with reference to the total number ofindividual and distinct monomeric units in the condensed chain, i.e.according to the formula IOOMA/(MA-t-Mp) where MA is the number of molsof a phenoxy compound (A) and Mp is the total number of m-ols of thosemonomeric compounds required for the known polymer. In the case ofcaprolactam, Mp would equal the total number of mols in this monomer;whereas with hexamethylene adipamide, MD would equal the total number ofmols of both hexamethylene diamine and adipic acid since one mol of eachis required to produce the monomeric salt. Likewise, with polyethyleneterephthalate, MIJ would equal the number of mols of terephthalic acidplus the number of mols of ethylene glycol.

The modifying compounds (A) of the present invention can be employedindividually or as mixtures, including precondensate salts or esterswith the known monomers or with each other. Some of the compounds (A)will form inner ammonium salts as indicated by such Z groupsas-NG5R1R2R3X9 or such D or E groups as -NBRH2X9, and these may also beused as monomeric reactants. Other salt type compounds include the metalsalts of the -SO3H substituent in any of the phenoxy side chains,preferably the alkali metal salts of potassium and sodium.

Depending upon the praticular hydrophilic group Z or the reactive groupD and E, a number of different effects can be observed, in thepolymerization or polycondensa- Ation reaction itself as well as in theproperties of the final polymer. Most importantly, of course, is theeffect of the Z group on the water absorptivity, dyeability, washabilityand antielectrostatic properties of the end product. These propertiesare improved and their relative values are increased With increasingconcentration of the built-in modi- 6 fying additives (A), and inaddition the hydrophilic properties of the polymer Will increase as thesubstituent Z itself increases in hydrophilic character. For example,the hydrophilic effect increases as one proceeds from the substituent -Hthrough -NRIRZ and -SO3Na to The substituent Z can also be selected suchthat polymers prepared with the modifying compounds (A) and processedinto filaments, fabrics or films will have more or less the character ofan ion exchange material, especially where there are ammonium or sulfiteions attached along the polymer chain.

The reactive groups D and E can influence the formation of the polyamideand polyester copolymers or mixed condensates in a number of differentways depending upon the particular substituents which are selected andthe manner in which they are condensed int-o the polymer. For example,if the substituents D and E are identical to each other, then thecompounds (A) are in most cases either diamines or dicarboxylic acids;if D and E are different, then an aminocarboxylic acid is present. Inthe latter instance, the compounds (A) can be added in larger amounts topolyamides or also to polyesters without causing any limitation of thechain growth, i.e. without having a stabilizing effect.

If the compounds (A) are either diamines or dicarboxylic acids, thenthey will act simultaneously as stabilizers in the production ofpolyamides and polyesters from the usual and known monomers having anequivalent number of the two reactive groups required for condensation.This stabilizing property can be extremely desirable since it leads tomelting-resistant polymers. In the case of lactam polymers and, forexample, when D and E signify the group -N9H2R'X9 in the additive (A),the reformation of monomers is strongly retarded so as to providestability against melting. The stabilizing effect can be veryadvantageously utilized where the additive (A) is used only in smallamounts, for example, under 0.5 molar percent.

If the compounds (A) as diamines -or dicarboxylic acids, are used inlarger amounts, preferably 0.15 to 2 molar percent, then thechain-breaking or stabilizing effect can be partly or completelynullified by a selective addition of a dicarboxylic acid to the diaminecompound or a diamine to the dicarboxylic acid compound. In order tosubstantially avoid stabilization while introducing relatively largeamounts of the compound (A), thereby providing maximum hydrophilicproperties, it is preferable to employ the compounds (A) in the form ofneutral salts. For this purpose it is possible, for example in the caseof polyamides, to add a diamine (A) as neutral salt of adipic acid.Correspondingly, it is also possible to add a dicarboxylic acid (A) asneutral salt of hexamethylene diamine. Finally, a neutral salt obtainedby combining a diamine (A) and a dicarboxylic acid (A) can be ernployedas the additive. In the polymerization of lactams, such an addition of aneutral salt to an anhydrous or water-free lactam yields the additionaladvantage of a very considerable catalytic acceleration of thepolymerization reaction. In the usual technological method of producingpolyethylene terephthalate, wherein glycol is employed in excess, thecompounds (A) can be added without difficulty either as freedicarboxylic acids or as dimethyl or diglycol esters.

Since basic or acid end groups can be generated in excess or inequivalent amounts in the polycondensates, or in conjunction withneutral end groups, the dyeability of polymer fibers can be variedwithin wide limits. In general, the copolymers or mixed condensates ofthe present invention can thus be given a controlled affinity for a widevariety of known dyestuffs.

As the neutralizing component in order t-o avoid stabilization by thecompounds (A) or to provide neutral end groups, any suitable acid,Iamine or alcohol ca-n be used, depending upon the group to beneutralized and the desired characteristics in the iinal product.(Conventional stabilizers can also be employed in the variouscondensation reaction.) For example, the neutralizing acid c-an .be adicarboxylic acid or its ester or among others, also phosphoric acid. Asthe neutralizing amine or alcohol, any suitable diamine or diol can beemployed. Those neutralizing compounds are preferably selected whichtake part in the polymerization either as fundamental monomers, or elsethose which are characterized by their hydrophilic properties. Accordingto the invention, `all of the compounds (A) can serve as neutralizerswith hydrophilic properties, but more common monomers may also beemployed such as: Iadipic acid or adipic 'acid este-r and terephthalicacid or terephthalic acid ester as acid types; hexamethylene diamine andxylylene ydiamine as amine types; and ethylene glycol and higheralkylene diols as alcohol types.

The installation of the compounds (A) into polyamide or polyester chainscan be accomplished under conventional reaction conditions forcondensation, transamidation or ester interchange. These reactions arealso possible for installation of the compounds (A) into the knownpolymers before spinning into laments, thereby providing :a graft orblock polymer. Depending on the type of fundamental known monomers andof the installabile groups D and E in the modifying compounds (A),various types of polymers can be produced 'which differ from oneIanother through the number of the modifying units per m-acromolecule,through the nature of the end groups and through the moleculardistribution. Furthermore, the polymerization and the resulting polymercan be influenced by the matter of whether the reaction is carried outin the absence of or in the presence of water and/or an additi-onalstabilizer such as a monofunctional-carboxylic acid, -amine 4or alcohol.

If, for example, a modifying diamine or dicarboxylic lacid of theformula (A) is added to a caprolactam polymerization in the p-resence ofwater, then each polymeric chain contains .at most one modifying unit,the end groups 'are predominantly or exclusively either amino groups orcarboxyl groups and the molecular distribution cu-rve is much narrowerthan without the additive in question. The amount of the additive isdetermined in this case by the particular chain length which is desired.If a modifying diamine of the formula (A) is used in the -form of anammonium salt, for example as the di-HCl salt, then it is possible tocarry out the caprolactam polymerization in a water-free medium, and theresulting polymers have a narrower molecular distribution and anespecially high melting stability. When the polymers produced in thethis manner contain only one molecule of the additive per macromolecule,the swelling value diminishes with increasing molecule size, i.e. withlonger polymer chains.

As diamines of the formula (A) suitable for the purpose of the presentinvention, the following compounds can be listed in detail:

NHz-CHz-CHz- -CHz-CHg-NH;

i CH3 As suitable dicarboxylic iacids or dicarboxylic acid esters of theformula (A), the following can be listed:

HOHzC-CHg-OOC-CHZ- GHz-COO-CHz-CHzOH l CH3 As a suitableamino-carboxylic acid of the formula (A), `an illustrative example wouldbe as follows:

For the production of the diamino compounds (A) p-cresol is used asinitial reactant and its Na-salt is brought into reaction with analky-lor alkylene-dihalide, preferably the brornides:

(1) ONa O-CmHzm-Br -i- Br-CmHzm-Br -I- NaBr l CH3 CH3 For theinstallation of the substituents D and E in 2,6-position of the benzenenucleus it is possible to convert the bromine ether of reaction (l) incold sulfuric acid with an N-methylol compound, as for exampleN-methylol benzamide, N-methylol phthalimide, N-methylol-e-capro lactam,almost quantitatively to the corresponding substituted2,6-bis-aminomethylcresol ethers, as for example:

O-CmHzm-Br NEI-CH2 CH2-4TH -l- 2H2O (I) O (I) O (36H5 06H5 Byconventional or readily understood reaction procedures, it is possible,finally, to replace the Br of the aliphatic ether chain by one of theabove-mentioned Z substituents. Thus, for example the compound (I/l)with Z=SO3Na is obtained by sulfonating the product of reaction (2) withsodium sulte in aqueous alcohol solution. The'cornpound (I/ 1) withZ=-N(CH3)CH2-CH2-SO3Na can be obtained if the nucleus-substitutedbromine ether of reaction (2) is converted with methyltaurin-Na indirnethylformamide, after which it is possible to convert Z bymethylation smoothly into The saponiication of the benzoyl compounds isaccomplished with concentrated strong alkali, that of the phthalimidocompounds by the hydrazine method.

For the preparation o-f the dicarboxylic acids (A), it is possible toproceed, for example, from 2,6-bis-methylolp-cresol, whose Na-salt isbrought into reaction with an alkylene dlhalide, preferably thebromides:

At temperatures of 50 to 80 C. it is possible by suitable `reactions toreplace the Br of the aliphatic ether chain by one of theabove-mentioned Z residues, in several ,reaction steps if necessary.Thus, for example, by sulfonating with sodium sulite in aqueous alcoholsolution there is obtained the sodium salt of the corresponding sulfonicacid. The methylol groups of the sulfonic acids obtained are thenconverted by means of hydrogen halide acids into chloromethylorbromometlhyl groups and these, over the dinitriles are converted underalkaline saponiiication into the corresponding dicarboxylic acids.

By hydrogenatingv the intermediate dinitriles, expediently withlithium-aluminum hydride, it is possible to readily obtain thecorresponding 2,6-bis-arninoethyl compounds.

For the production of dicarboxylic acids (II/3), the 2,6-bis-methylhalide compounds are converted with w-methyl-aminocapronitrile in ether,and the dinitrile is saponified with strong alkali.

The arnino-acids (A), such as the compound (Ill/0), are .also readilyaccessible since the above-mentioned 2,6-bis-monomethyl compounds can beconverted on one side with potassium phthalimide. After replacement ofthe remaining Br by -CN and preferably after completion of thesubstitution on the aliphatic ether chain, the amino lacids are obtainedby an expediently gradual saponication.

-The properties of some of the compounds to be used according to theinvention are described immediately below. The chemical designation ineach case is preceded by an abbreviated designation or code number inorder to simplify a later reference to these compounds in the workingexamples. The residue p-CH3-C6H4-O- is designated as the p-cresoxygroup.

(I) Diamines (U00): Diamine of structure ('I/O) with Z=H; 1-[2,6-bis-aminomethyl-presoxy] -n-hexane Colorless, viscous oil withstrongly basic properties, boiling point of to 170 C. at 0.05 mm. Hg.Neutral salt with adipic acid: White powder soluble in Water andmethanol, melting point of 183 to 185 C.

(I/ 10): Bis-benzoyl diamine of structure (I/ 1) with Z=H;1-[2,6-bis-benzoylaminomethyl p cresoxy]-nhexane. Colorless needles fromethanol-Water, melting point of 152 to 153 C.

(I/01): Diamine of structure (I/O) with Z=SO3Na; 1-[2,6bisaminomethyl pcresoxy]-n-hexane-sulfonic acid-(6) sodium. The HCl salt of thesodium-free compound forms colorless needles from Water, melting pointof 254 to 256 C. It binds table salt in stoichiometric amounts duringcrystallizationfrom NaCl solutions. The salt, consisting of 1 moldiamine (I/01) and 1 mol adipic acid, forms a white, water-solublepowder, melting point of 220 to 225 C.

(I/ 11): Bis-benzoyldiamine of structure (I/l) with Z=SO3Na;1-[2,6-bis-benzoylaminomethyl p cresoxy]- n-hexane-sulfonic acid-(6)sodium. Colorless needles from 5% table salt solution, melting point of215 to 218 C.

(I/OZ): Diamine of structure (I/O) with [2,6-bis-aminomethyl pcresoxy]hexamethyleneN,N methyl-taurino. Strongly alkaline oil. Thedi-HCl salt forms a colorless, hygroscopic powder without a definedmelting point.

(I/12): Bis-benzoyldiamine of structure (I/l) withZ=N(CH3)-CH2-CH2-SO3H; [2,6 bis benzoylaminomethyl pcresoxy]-hexamethylene-N,N-methyltaurine. Colorless needles fromalcohol-Water, melting point of 147 to 148 C.

(I/13): Bis-benzoyldiamine of structure (I/l) withZ=N(CH3)2-CH2-CH2-SO39; [2,6 bis benzoylaminomethyl p cresoxy]hexamethylene dimethyltaurobetaine. Colorless needles fromalcohol-water, melting point of to 173 C.

(I/ 41): Bis-benzoyldiamine of structure (I/4) with Z=SO3Na;1-[2,6-bis-benzoylaminomethyl p cresoxy]- n-decansulfonicacid-(10)sodium. Colorless needles from alcohol-water, melting point of192 to 193 C.

11 (I/SO): Diamine of structure (I/ with ZII-I; 1-[2,6bisaminoethyl pcresoxy]nhexane. Colorless, viscous oil with strongly basic properties,distillable without decomposition, boiling point of 170 to 175 C. at0.03 mm. Hg. Neutral salt with adipic acid: colorless fromalcohol-ether, melting point of about 150 C.

(II) Dicarboxylic acids (II/00): Dicarboxylic acid of structure (Il/0)with Z=H; 1-[2,6-bis-ca-rboxymethyl p cresoxy]nhexane. Not readilysoluble in water; long, colorless needles from water, melting point of139 to 140 C. Neutral salt with hexamethylene diamine: water-solublepowder, melting point of 194 to 195 C.

(II/01): Dicarboxylic acid of structure (II/0) with Z=SO3Na; 1-[2,6 biscarboxymethyl p cresoxy]n hexane-sulfonic 'acid-(6) sodium. Colorlessneedles from water, melting point of 225 to 226 C. Neutral salt withhexamethylene diamine; colorless needles from water, melting range 215to 220 C.

(II/11): Dimethyl ester of dicarboxylic acid (II/0l). Colorless needlesfrom methanol, melting point of 230 to 233 C.

Salts from diamines (I) and dicarboxylic acids (II) It is, inparticular, an object of the present invention to use salts from thediamines (I) as additives for polycondensates. In some cases, thesesalts do not need to be isolated, but can be produced in aqueoussolution and added directly to the condensation reaction. If necessary,the inorganic neutral salts formed, e.g. in the production of thesolutions, can be removed by means of ion exchangers. Several -of thesalts formed from diamines (I) and dicarboxylic acids (II) are listedbelow with their properties:

Salt from (I/OO) and (II/00): White powder, diicult to dissolve inwater; melting point of 105 to 110 C.

Salt from (I/00) and (II/01): White, water-soluble, dry powder; meltingpoint of 60 to 65 C.

Salt produced from 1 mol HC1 salt of (I/Ol), 1 mol (II/01) and 2 molsNaOI-I: White, Water-soluble, dry powder; melting point of 175 to 180 C.

Salt produced from 2 mols HC1 salt of (I/01), 1 mol (II/01) and 2 molsNaOH: Colorless, water-soluble needles; the melting point is dependenton the kind of heating and is about 140 C. as the immersion meltingpoint and about 190 to 200 C. with a slow rise in temperature.

(III) Amino acids (III/00); Amino acid of structure (III/0) with Z=H; 1[2 aminomethyl 6 carboxymethyl p cresoxy] nhexane. White, linecrystalline powder, not readily soluble in water, melting point of 170to 175 C.; forms a nitrate, not readily soluble as colorless needleswith melting point of 161 to 162 C.

The present invention is more fully illustrated by the followingexamples and tables. The accompanying drawing also provides a graphicalrepresentation of comparative results. These examples are directed toparticular species of the modifying compounds (A), and it will beunderstood that such examples are not intended to be the exclusivepractice of the invention. Example is a standard polyamide and Example13 is a standard polyester, i.e. the modifying compound (A) was omittedin these examples so as to provide a basis for comparison. In theremaining examples, the modifying compound (A) is identied by its codenumber as employed in the irnmediately preceding paragraphs.

As will be recognized from the following examples and comparisons, thepresent invention provides substantial and controllable improvements insuch secondary ber properties of polyamides and polyesters as theirwaterabsorptivity, washability, dyeability and electric conductivity.These improvements are furthermore realized at relatively low cost sinceonly a small proportion of the modifying compounds is required and thesemodiers can be condensed or linked into the polymer chain with con-Ventional process steps.

Example 1 22.6 grams of water-free e-caprolactam are heated under anitrogen vacuum of 3 to 4 mm. Hg in a sealed glass tube with 1.0 molarpercent of the neutral salt of the diamine (I/0 0) and the dicarboxylicacid (II/00), with occasional shaking, for 24 hours at 220 C. Aftercooling, the polyamide is ground, extracted with methanol for 18 hoursand dried.

Example 2 The polyamide is prepared as in Example 1, but with the use of5.0 molar percent of the neutral salt of the diamine (I/00) anddicarboxylic acid (II/00).

Example 3 The polyamide is prepared as in Example 1, but with the use ofthe neutral salt of the diamine (I/00) and the dicarboxylic acid(II/01).

Example 4 The polyamide is prepared as in Example 1, but with the use ofthe neutral salt of the diamine (I/01) and adipic acid.

Example 5 The polyamide is prepared as in Example 1, but with the use ofthe neutral salt of the diamine (I/ 01) and the dicarboxylic acid(II/01).

Example 6 The polyamide is prepared as in Example 1, but with the use ofthe neutral salt of hexamethylene diamine and the dicarboxylic acid(II/01).

Example 7 The polyamide is prepared as in Example 1, but with the use ofthe neutral salt of the diamine (I/02) and adipic acid.

Example 8 The polyamide is prepared as in Example 1, but with the use ofthe neutral salt of the diamine (I/02) and and the dicarboxylic acid(II/01).

Example 9 The polyamide is prepared as in Example 1, but with the use ofthe amino acid (III/00).

Example 10 This is a comparative example of a polyamide prepared withoutincorporating a modifying additive of the invention. 4.5 kilogramse-caprolactarn are kept with 0.5 kilograms of Water in the presence of0.15 molar percent benzoic acid as a polymerization stabilizer underexclusion of air and under their own pressure of about 10 atmospheres(gauge) in a 10-liter autoclave for 1.5 hours at 220 C. During anadditional 1.5 hours, pressure is released to normal and thepolymerization is terminated by 4 to 5 hours of washing with nitrogen at220 C. The polymer is drawn off as an extruded rod, cut up into shortlengths and extracted by repeated boiling for several hours with water.

Example 11 4.5 kilograms e-caprolactam are kept with 0.5 kilogram waterin the presence of 0.75 molar percent of the neutral salt of the diamine(I/OO) and the dicarboxylic acid (II/01) under exclusion of air and attheir own pressure of about 10 atmospheres (gauge) in a 10-literautoclave for 1.5 hours at 220 C. During an additional 1.5 hours,pressure is released to normal and the polymerization is completed by 4to 5 hours of washing with nitrogen at 220 C. The polymer is drawn offas an extruded rod, cut up into short lengths and extracted by repeatedboiling with water for several hours.

13 Example 12 The polyamide is prepared as in Example 1l, but with theuse of the neutral salt of the diamine (I/Ol) and the dicarboxylic acid(II/01).

Example 13 This is a comparative example of a polyester prepared Withoutincorporating a modifying additive of the invention. 100 grams dimethylterephthalate are heated with 100 inl. of ethylene glycol in thepresence of 0.02% by weight of antimony trioxide and 0.015% by weight ofzinc acetate under nitrogen in a vessel equipped with an agitator forabout 2 hours at 240 to 250 C., in which process about 55 ml. ofmethanol are distilled off. After application of a vacuum, which isfinally raised to about 0.3 mm. Hg, the excess glycol is distilled off,the temperature raised to 275 to 278 C., and the increasingly viscouscondensate is fully condensed in about 1.5 hours. The cooled product wasground into a powder.

Example 14 100 grams dimethyl terephthalate are ester-interchanged with100 ml. ethylene glycol with removal of methanol as described in thesecond sentence of Example 13. After addition of 2 molar percent 'of thedicarboxylic acid (II/O1), dissolved in 15 to 20 ml. glycol, the processis continued as described in Example 13.

The properties of the polyamides and polyesters prepared according tothe foregoing examples are compared in Tables 1-5 as set forthhereinbelow.

In Table 1 the properties of the polyamides produced in Examples 1 to 9and lof the comparative condensate of Example are contrasted. The lactamconversions vare between 92 and 94% in all of the examples. The solutionviscosity values Zn are measured in 82.5% formic acid in Ostwaldviscosimeters and are extrapolated to zero concentration. The valueslisted in Table 1 for the waterabsorption capacity, i.e. swelling value,were determined in powders of equal grain size (sifted to 03.5 to 0.8mm.) according to DIN 53814 E. In stretched filaments, the swellingvalues correspond to the values measured with the polymers in the formof powders, as will be apparent by comparing the data of Tables 1 and 2.Since the dyeability, dry moisture absorption and the electricalconductivity in the condensates will vary in magnitude in lconformanceWith the swelling value, the swelling values listed in Table 1 alsoprovide an accurate measure for such additional properties, not only inpowders, but also in stretched filaments. In this connection, Tables 3and 4 present some additional comparative data obtained 14 withstretched filaments containing various additives or no additive (Example10).

Table 1 shows, in particular, that the swelling value increases stronglywith increasing concentration of the modifying additives and withincreasing concentration of the hydrophilic groups Z. The melting pointof the condensates remains very nearly unchanged within a relativelybroad range of additive concentrations.

Table 2 discloses that the primary textile properties of the filaments(tensile strength and elongation) are not substantially affected by theadditives.

Table 3 illustrates the effect of the modifying additives upon thedyeability of the polyamides as textile fibers and the substantialchange in affinity for different dyestufs.

In Table 4, there are presented the moisture absorption at relativehumidity and the electric resistance of textile fibers for thepolyamides of Examples 10, 11 and 12. With increasing concentration oflthe additives, the moisture absorption increases while the electricresistance diminishes. As will be recognized, the antielectrostaticbehavior of the polymer will improve with increasing electricconductivity. The measurement of electric resistance was carried out insamples which were conditioned at 22 C. and 65% relative humidity andwere freed of the preparation.

For textile uses, the absorption capacity of a fabric or material is ofspecial interest because of its relation to the washability of thefibers or fabric. In fabrics made of the material of Examples 10 and 12,by immersion in distilled water which contained 1% Nekal 1, theabsorption capacity was determined with respect to the time ofimmersion. It was found that the absorption capacity of the materialcontaining the modifying additive (Example 12) increases rapidly withina relatively short immersion time to a multiple of the correspondingvalue for the comparative material (Example 10), as shown in theaccompanying drawing in which the height of absorption is plottedagainst the immersion time. This effect can be still furtherconsiderably strengthened by dyeing of the fabric.

Table 5 presents some ofthe properties of polyethylene terephthalateswith and without a modifying additive according to the invention by wayof comparison. The solution viscosities 11,51 (relative viscosities) aremeasured in Ostwald viscosimeters for 1% solutions in ni-cresol at 25 C.The swelling values were determined with powders in the saine manner asin the above-mentioned polyamides.

1Nekal is a trademark under which Badische Anilin und TABLE 1[Properties of the e-caprolactain condensates of Examples 1 to 9 ascompared to a standard condensate (Example 10), measured in powders ofequal grain size] l Additive Swelling Melting point Example AdditiveType of substituent Z concentration, Z1,.102 value, percent in C.

mol percent 10 gie omparative condensate 7.4 13 21o-218 2 E: 7.4 i0212-213 E 5 l( 4.7 24 203-205 'i 1 4 oaa i i 7-5 21 212-213 03 2 dip p 16.7 2i 2li-213 01, o3 a 1 6 g/oi soaNa 60 24 210'212 PXm iI/oi soaNa 1 i7-6 20 214-216 7 K912i, N(CH3) (CH2)TSO3H il* 6 a 22 2li-213 1 r8 I/02N(CHa)-(CH2)2-SO3H 1 m01 SOSN, 1 6.7 2e 212-213 Q III/00- H. 1 10. 0 17212-214 TABLE 2 [Mechanical properties of e-caprolactam condensates fromExamples 11 and 12 as compared to a standard condensate (Example 10)measured on stretched filaments, denier 60/12. Concentration of theadditives in each case is 0.75 mol. percent. Solution viscosity ismeasured with the extracted cuttings. The tensile strength is measuredin Reiss-Kilometers (Rkm.).]

Amt in Z1. 102 Swelling Melting Stretch Tensile Elongation, ExampleAdditive mol value, point, C. ratio strengt percent percent percent(Rlnn.)

TABLE 3 wherein:

[D bn f the p l t m co d msm fE a los u d 12 as Z is a member selectedfrom the group consisting of hyye. llyO E'Ca T0303 1'1 G SO X mp ancompared to a standard condensate (Example 10), judged in a fabric 20drogen, *SOSH and lS alkah metal and ammOIllUm Acid Wool DispersionBasic yestu D and E 'each represent a react1ve substltuent capable ofExilim- Additive A tllyelstugbl Clyesttliif erlint condensing saidmodifying compound into said linear p e n 31 ue l c e Bflllelll, 25polymer chain and selected from the group consisting of NHR', NHAeyl,*NeR'HZXQ NeR'H2so3e, Good Good Very slight. }Fair Strong Moderate.-N--C O }Weak Very strong... Do. \(C2)y NR' CH2y-Cooa", -CooR" and-COO-CH2CH2OI-I TABLE 4 [Moisture absorption at 100% relative humidityand electric resistance 35 gr c.,1 65g, rertlige humidity)d Eftnetecprgiaetm eoidsates f G represents a member selected from the groupconsisting Kamp eS 3.111 aS Compare 0 a S all ar C011 @DS3 e Kamp e 10),measured on stretched filaments denier 60H2] of alkyl of 1 to 24 carbonatoms, phenyl and said alkyl and said phenyl substituted by -O-CmH2m-Z;

c R1, R2 and R3 each represent a substituent selected from ExampleAdditive ags' Eleicltlrfggn 40 the group consisting of hydrogen, loweralkyl and Percent by weight phenyl;

R `and R each represent a substituent selected from the 12 12 140 m isIan integer of from 1 to 24, inclusive, with the proviso that m is atleast 6 where X is hydrogen;

n is an integer of from O to 12, inclusive; and y is an integer of from1 to 8, inclusive. TABLE 5 2. A synthetic ber-forming polymer as claimedin claim 1 wherein the polymer contains from 0.2 to 2 molar [Propertiesof polyethylene terephthalates with and Without addition of n thedicarboxylic acid (II/01), measured in powders of grain size 0.5 perce tof sald Ompound atmg. as a modlfymg umt to 0.8 mm] 3. A synthetic`fiber-forming linear polymer as clalmed in claim 1 wherein there iscondensed into the polymer chai th co Exam- Amount Swelling Sotening n empound ple Addltive in mol me l value, paoiit, 5 5

percent percent O (CHZ) o S ozNa 13 None 1. e3 5.4 259-260 14 II/oi2.o 1. 53 7.3 257-258 H00CCH2 CH2-COOH The invention is hereby claimedas follows: H3 1. A synthetic liber-forming linear polymer selected fromthe group consisting of polyamides -and polyesters containing as `amodifying unit condensed into the linear 4. synthet1c ber-forming linearpolyamide polymer polymer chain from 0,1 t0 10 molar percent 0f at least65 as claimed 1n clalm 1 wherem there is condensed into one Compound 0fthe formula the polymer chain the compound O--CmHzm-Z O-(CHz)-SO3N3D-CnHzn CnHzn-E NH2*CH2 CH2-NH2 H5 CH3 -17 5. A synthetic fiber-forminglinear polyamide polymer as claimed in claim 1 wherein there is-condensed into the polymer chain the compounds HOOG-CE2 -CHz-COOH 8. Asynthetic fiber-forming linear polyamide polymer 40 18 as claimed inclaim 1 wherein there is condensed into the polymer chain the compound9. A synthetic fiber-forming linear polyamide polymer as claimed inclaim 1 wherein there is condensed into the polymer chain the compound lCH3 10. A synthe-tic fiber-forming linear polyamide polymer as claimedin claim 1 wherein there is condensed into the polymer `chain thecompound NH2-CH2 CH2-COOH References Cited by the Examiner UNITED STATESPATENTS 2,894,934 7/1959 Burkhard 260-75 2,902,475 9/ 1959 Burkhard260-78 3,006,899 10/ 1961 Hill et al. 260-78 WILLIAM H. SHORT, PrimaryExamlz'ner.

LOUISE P. QUAST, Examiner.

1. A SYNTHETIC FIBER FORMING LINEAR POLYMER SELECTED FROM THE GROUPCONSISTING OF POLYAMIDES AND POLYESTERS CONTAINING AS A MODIFYING UNITCONDENSED INTO THE LINEAR POLYMER CHAIN FROM 0.1 TO 10 MOLAR PERCENT OFAT LEAST ONE COMPOUND OF THE FORMULA